Bleach follows the story of Kurosaki Ichigo, a substitute Shinigami, across a variety of themes and landscapes. The punk protagonist is supported by a litany of side characters, many of whom he must inevitably save due to the standard Shōnen trope of "protecting one's friends."

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Running for over slightly over 15 years, Bleach has taken readers and viewers on an elaborate, and meaningful, journey — with several key moments lending shape to future arcs. Here are ten of the most crucial events in the series that deeply affected the direction of the story.

10 When Rukia Stabs Ichigo The First Time

Ichigo & Rukia - Bleach

The story only really begins at this moment. Rukia, severely injured by vicious Hollows, has only one option left to her. She tells the ordinary human boy standing next to her that he could fight off the attackers with half of her reiatsu transferred into his body. The only way to do this however, is to be stabbed by her Zanpaktou.

Ichigo takes the plunge, forcing the blade into himself. This results in an explosion of blue light, and Ichigo Kurosaki, the Substitute Shinigami, is born.

9 When Soul Society Realizes Aizen’s Betrayal

Aizen fakes his way through Seiretei's hierarchy, becoming a beloved captain (in fact, Kubo has stated that he taught a calligraphy class so popular that students sat in the hallway because the class was so crowded.) Given this, it came as a personal shock to most Shinigami to see their favorite leader murdered.

When Aizen's deception was exposed by Captain Unohana, the resulting trauma was considerably worse; especially since Captains Gin and Tousen were also on his side.

8 When Aizen Stops Ichigo’s Bankai

Aizen stops Ichigo's Zangetsu with one finger

Ichigo had just finished an exhausting fight with Captain Byakuya, in which he reveals his bankai, Tensa Zangetsu for the first time. His opponent commends him for his strength as well as his masterful control of his bankai. This praise does not come lightly, as Byakuya has almost never been defeated.

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So, when Ichigo charges at Aizen in a later scene, burning with anger, viewers were expecting him to pummel the latter to the ground. However, Aizen effortlessly stops Tensa Zangetsu with a single finger — simultaneously pausing Ichigo's tough guy background music — evidence of his terrifying levels of power.

7 When Isshin Comes Out As A Shinigami

Isshin Kurosaki in Bleach

A common feature of Shōnen anime is the importance of legacy; the reason behing Ichigo's ability to call on a Zanpaktou being his father. In the real world, Kon is roaming around the streets in Ichigo's body. He is suddenly attacked by Grand Fisher, the Hollow (now botched Arrancar) who killed Masaki Kurosaki.

As he is about to land the final blow, a shield suddenly appears around Kon-Ichigo. The source is soon revealed to be Isshin Kurosaki, walking towards Grand Fisher in full Shinigami regalia. This set the stage for a lot that happens in the series, including Aizen's earlier (indirect) involvement in Ichigo's complicated genetics.

6 When Ichigo Destroys Ulquiorra

ulquiorra vs ichigo in Bleach

Near the end of the Arrancar arc, Ichigo, Uryuu and Orihime are trying to fight off Ulquiorra's Segunda Etapa atop the fortress of Las Noches. All seems lost when Ichigo gets a hole blown through his body, but Orihime's screams activates something inside him, producing the fearsome Vasto Lorde Ichigo.

In this form, he deflects Ulquiorra's lance attacks with ease, and even manages to outpace him using the Sonido technique. The fight is pretty much over when Ichigo slashes through his enemy's body, and adds an explosive Cero at point-blank rage (to seal the deal.)

5 When Old Man Yamamoto Is Defeated

Yamamoto - Bleach

Yamamoto was said to be the strongest Shinigami in a thousand years, a claim he backed with his indomitable spirit, and, of course, Ryuujin Jakka. His bankai, Zanka no Tachi, is considerably more dangerous, given that one of its side-effects is the potential destruction of Soul Society if kept on for too long.

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After such a display, it came as a rude awakening to see Yhwach simply slice through the old man as if he were made of butter. With Yamamoto dead, the other Captains had lost their resolve.

4 When The First Kenpachi Is Revealed

yachiru unohana bleach

Zaraki Kenpachi is the 11th of his line, having won his position by killing the previous Captain of the 11th division with a single strike. This tradition convinced fans that none of the Kenpachis were alive, but Kubo was ready with a twist.

After Yhwach's attack devastated Sereitei, Kyoraku asked for permission from the Central 46 to allow him to train Zaraki, calling him one of their last hopes. After compelling them to agree, he brings in Unohana Retsu, Captain of the medical division, finally revealing that she was the first to hold the title of Kenpachi.

3 When Ichigo Discovers His Heritage

Masaki Kurosaki in Bleach.

Through a slightly convoluted storyline, Isshin Kurosaki explains how he and Masaki had originally met fighting an extremely powerful Vasto Lorde, mysteriously present in the real world.

He goes on to tell Ichigo that his mother was one of the last members of a Quincy pure blood line, confessing that he had Yhwach's blood flowing through him on his maternal side. This makes Ichigo a human-Shinigami-Hollow-Quincy hybrid, and gives him the necessary ammunition to fight Yhwach.

2 When Yhwach Explains ‘A for Almighty’

As Yhwach is fighting Ichigo, he explains that the letter 'A' denoting his status stands for The Almighty. He adds that with this power, he is nigh invincible, because he can not only see into the future, but also choose a single thread from an infinity of timelines in which his victory is guaranteed.

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This ups the ante by a mile, because none of the characters have a single weapon that could possibly be used to counter timeline-abduction. It takes the unexpected combination of Ichigo, Uryuu and Aizen to finally bring an end to Yhwach's omnipotence.

1 When Zaraki Kenpachi Unleashes His Bankai

Kenpachi - Bankai - Bleach

There is no doubt anymore that Zaraki Kenpachi is the strongest captain in the Gotei-13 (after Yamamoto and Unohana are killed.) His Zanpaktou release first came while fighting Gremmy, the Imagineer who could convert his fantasies into reality.

However, only when he is faced against an impossible opponent, Gerard Valkyrie, does Yachiru appear to save Kenpachi. She asks him to release his Bankai, which turns him into a red demon with a broken sword. In this state, Kenpachi cuts Gerard in half with a single strike.

NEXT: Bleach: The 10 Most Tragic Backstories In The Series, Ranked